Model-based Wiki

This web applies a Model-based Wiki (MBW) to the problem
of documenting MBW itself (recursion: see recursion).

Getting Started

The MBW Introduction page offers a concise, if somewhat chewy,
introduction to the way that this TWiki web is constructed.
In case you're not ready to tackle that page, however, here's a precis:

Model-based Wiki (MBW) provides both an organizational approach and some handy support software
for documenting complex systems in TWiki.
Because a "model" of the system is used to structure the documentation,
construction and use (eg, navigation) of the documentation
are based on (and help to clarify) the system's architecture.

Basic Concepts

MBW is based on four concepts from graph theory
and Object-Role Modeling:
nodes, edges, roles, and views.
The generality and simplicity of these concepts make it (relatively) easy
to model the structure of a very wide variety of systems.
Once the structure has been modeled,
detailed information can be added to appropriate pages.

A node represents a part of the system being documented. This might be a computer, database, file, program, etc.

An edge represents a relationship between (sets of) nodes. This might be an API, a network connection, etc.

Each edge has two or more active roles, filled by specified nodes. Typically, the first two roles are the edge's "source" and "target" (eg, the sender and receiver of a message). Complex relationships may require more roles, however, so MBW allows up to five roles per edge.

A view presents a topical subset of the available nodes and edges (ie, a subgraph). The topic might be a shared activity (eg, system restart), a common attribute (geographic location), etc.

Although MBW demands that TWiki pages be constructed in a specific manner
and contain specific information, MBW makes it easy to create such pages.
Then, because the information is available in a machine-friendly format,
it can provide user-friendly diagrams, indexes, links, etc.

MBW's cross-linking and indexing facilities allow documentors
to create richly-linked sets of pages whose overall structure
correspond closely to that of the system being documented.
They also encourage the "Don't Repeat Yourself" (DRY) approach:
because content (eg, Precis, Summary, Title) from each page
can be easily viewed on other pages,
it doesn't need to be repeated there.